It is wrong to terminate a pregnancy because it is killing a human life. A baby is alive at every stage of pregnancy. There is not some magical week in the pregnancy when the baby becomes real. A baby is alive and real from the moment of conception. If the mother or the parents feel that they are not in a position to raise a child, then that child may be given up for adoption.
I believe killing an unborn human is wrong. Just because they haven't been born yet doesn't mean they aren't human and don't have a right to live. It is murder. If you are financially unable to support the child, you could at the very least leave it in a foster home. I don't believe we have the right to create life and destroy it as we see fit.
The decision to terminate a pregnancy is not a black and white issue. A blanket proposition that terminating a pregnancy is always wrong is misplaced. For example, terminating a pregnancy may be necessary to preserve the life of the mother, a procedure that even most religious organizations permit. At the other extreme, using abortion as a means of birth control is not appropriate.
The problem with assigning right and wrong to such an area as abortion is that it demonstrates a complete lack of regard for all of the gray factors that go into a decision to terminate a pregnancy. Sometimes the timing just isn't right. Sometimes people are just not financially stable. Sometimes there are health issues that make it dangerous for a woman to carry a baby to full term or even the development of the baby could take a turn that make terminating the pregnancy may be a better choice at that time than continuing it. Sometimes pregnancies are the result of unwelcome sexual encounters. The decision to terminate a pregnancy is never easy and there are far too many factors to consider to label the decision to do so merely right or wrong.